world leaders, including president obama are in attendance at the memorial service. let's go live to david mackenzie who is live in johannesburg, south africa. >> it has been a special day here in south africa. the commemorative ceremony for nelson mandela. he died at the age of 95. he spent more than 20 years in prison. he brought africa into a free presents. it has been an incredible day but that did not stop thousands streaming in to remember him. more than 90 world leaders and statesmen came man to pay their respects. president barack obama gave a very moving account of his connection with nelson mandela and what he meant to a lot of people. >> some of the world's most powerful and employed two people came here. >> i am not a saint unless you think of a saint as a sinner who keeps on. >> the festivities, the come member to raise cash as it had been a moment of morning but he was sick for months before and they were expecting his passing. >> it is incredible to get a perspective on a number of people. i know the stadium could hold up to 90,000 people. we're talkin